what the hell is a nug i keep hearin people say it but i dunno what it means. im good on most other words its just this one i got trouble with.
1 Improper use of contact lenses or steroid eyedrops can lead to fungal infections, which in turn can cause corneal ulcers. Also, a corneal injury that results in plant material getting into the eye can lead to fungal keratitis.  Acanthamoeba are microscopic, single-celled amoeba that can cause human infection.
Tiny tears to the cornea may also cause corneal ulcers. These tears can come from direct trauma, scratches or particles such as sand, glass or small pieces of metal. Such injuries damage the cornea and make it easier for bacteria to invade and cause an ulcer.